2008 GMC SIERRA Owner's Manual

Safety Belt Reminders
Safety Belt Reminder Light
When the engine is started, a chime will sound for
several seconds to remind people to buckle their safety
belts. The driver safety belt light will also come on
and stay on for several seconds, then it will ash for
several more. You should buckle your seat belt.
This chime and light will be
repeated if the driver
remains unbuckled and the
vehicle is in motion.
If the driver’s belt is buckled, neither the chime nor the
light will come on.
Passenger Safety Belt Reminder Light
For vehicles with Passenger Safety Belt Reminder
Lights, several seconds after the engine is started, a
chime will sound for several seconds to remind the front
passenger to buckle their safety belt. This would only
occur if the passenger airbag is enabled. SeePassenger
Sensing System on page 1-80for more information.
The passenger safety belt light will also come on
and stay on for several seconds, then it will ash for
several more.
This chime and light are
repeated if the passenger
remains unbuckled and
the vehicle is in motion.
If the passenger’s safety belt is buckled, neither the
chime nor the light will come on.
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Airbag Readiness Light
There is an airbag readiness light on the instrument
panel cluster, which shows the airbag symbol. The
system checks the airbag’s electrical system for
malfunctions. The light tells you if there is an electrical
problem. The system check includes the airbag
sensor, the pretensioners, the airbag modules, the
wiring and the crash sensing and diagnostic module.
For more information on the airbag system, seeAirbag
System on page 1-68.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds.
The light should go out
and the system is ready.
If the airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your
airbag system may not work properly. Have your vehicle
serviced right away.{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away if the airbag
readiness light stays on after you start your
vehicle.
The airbag readiness light should ash for a few
seconds when you start the engine. If the light does not
come on then, have it xed immediately. If there is a
problem with the airbag system, an airbag Driver
Information Center (DIC) message may also come on.
SeeDIC Warnings and Messages on page 3-63for
more information.
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Airbag Off Light
If your vehicle has an airbag on-off switch, it also has a
passenger airbag status indicator located in the
overhead console.
When you start your vehicle, the passenger airbag
status indicator will light ON and OFF, or the symbol for
on and off, will light for several seconds as a system
check. Then, after several more seconds, the status
indicator ON or OFF, or either the on or off symbol, will
light to let you know the status of the right front
passenger’s frontal airbag.When you turn the right front passenger’s airbag off,
this light will come on and stay on to remind you that the
airbag has been turned off. This light will go off when
you turn the airbag back on again. SeeAirbag Off
Switch on page 1-76for more on this, including
important safety information.
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Canada
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When you manually turn the right front passenger’s
airbag off using the airbag on-off switch in the glove box,
the indicator light OFF or the off symbol will come on
and stay on to remind you that the airbag has been
turned off. This light will go off when you turn the airbag
on. SeeAirbag Off Switch on page 1-76for more on
this, including important safety information.
{CAUTION:
If the right front passenger’s airbag is turned
off for a person who is not in a risk group
identied by the national government, that
person will not have the extra protection of an
airbag. In a crash, the airbag will not be able to
inate and help protect the person sitting there.
Do not turn off the passenger’s airbag unless
the person sitting there is in a risk group
identied by the national government. See
Airbag Off Switch on page 1-76for more on this,
including important safety information.
{CAUTION:
If the airbag readiness light ever comes on
when you have turned off the airbag, it means
that something may be wrong with the airbag
system. The right front passenger’s airbag
could inate even though the switch is off. If
this ever happens, do not let anyone whom the
national government has identied as a
member of a passenger airbag risk group sit in
the right front passenger’s position (for
example, do not secure a rear-facing child
restraint in the right front passenger’s seat)
until you have your vehicle serviced. See
Airbag Off Switch on page 1-76andAirbag
Readiness Light on page 3-38for more on this,
including important safety information.
If the word ON or the on symbol is lit, it means that the
right front passenger’s frontal airbag is enabled (may
inate). SeeAirbag Off Switch on page 1-76for more on
this, including important safety information.
If, after several seconds, both status indicator lights
remain on, or if there are no lights at all, there may be a
problem with the lights or the airbag on-off switch.
See your dealer/retailer for service.
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Passenger Airbag Status Indicator
If your vehicle has the passenger sensing system, your
overhead console will have a passenger airbag
status indicator.
When you start the vehicle, the passenger airbag status
indicator will light ON and OFF, or the symbol for on
and off, for several seconds as a system check. Then,
after several more seconds, the status indicator will
light either ON or OFF, or either the on or off symbol to
let you know the status of the right front passenger’s
frontal airbag.If the word ON or the on symbol is lit on the passenger
airbag status indicator, it means that the right front
passenger’s frontal airbag is enabled (may inate).
{CAUTION:
If the on indicator comes on when you have a
rear-facing child restraint installed in the right
front passenger’s seat, it means that the
passenger sensing system has not turned off
the passenger’s frontal airbag. A child in a
rear-facing child restraint can be seriously
injured or killed if the right front passenger’s
airbag inates. This is because the back of the
rear-facing child restraint would be very close
to the inating airbag. Do not use a rear-facing
child restraint in the right front passenger’s
seat if the airbag is turned on. United States
Canada
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{CAUTION:
Even though the passenger sensing system is
designed to turn off the right front passenger’s
frontal airbag if the system detects a rear-facing
child restraint, no system is fail-safe, and no
one can guarantee that an airbag will not deploy
under some unusual circumstance, even
though it is turned off. We recommend that
rear-facing child restraints be secured in the
rear seat, even if the airbag is off.
If the word OFF or the off symbol is lit on the airbag
status indicator, it means that the passenger sensing
system has turned off the right front passenger’s frontal
airbag. SeePassenger Sensing System on page 1-80
for more on this, including important safety information.If, after several seconds, both status indicator lights
remain on, or if there are no lights at all, there may be a
problem with the lights or the passenger sensing
system. See your dealer/retailer for service.
{CAUTION:
If the airbag readiness light in the instrument
panel cluster ever comes on and stays on, it
means that something may be wrong with the
airbag system. If this ever happens, have the
vehicle serviced promptly, because an
adult-size person sitting in the right front
passenger’s seat may not have the protection
of the airbag(s). SeeAirbag Readiness Light
on page 3-38for more on this, including
important safety information.
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Charging System Light
This light will come on
briey when you turn on
the ignition, but the engine
is not running, as a
check to show you it is
working.
It should go out once the engine is running. If it stays
on, or comes on while you are driving, you may have a
problem with the charging system. A charging system
Driver Information Center (DIC) message may also
appear. SeeDIC Warnings and Messages on page 3-63
for more information. This light could indicate that you
have problems with a generator drive belt, or another
electrical problem. Have it checked right away. If
you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and air conditioner.
Voltmeter Gage
Your vehicle may have a
voltmeter gage.
When the ignition is on, this gage indicates the battery
voltage.
When the engine is running, this gage shows the
condition of the charging system. The gage may
transition from a higher to lower or a lower to higher
reading, this is normal. If the vehicle is operating outside
the normal operating range, the charging system light
will come on. SeeCharging System Light on page 3-43
for more information. The voltmeter gage may also
read lower when in fuel economy mode. This is normal.
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Readings outside the normal operating range may also
occur when a large number of electrical accessories
are operating in the vehicle and the engine is left idling
for an extended period. This condition is normal
since the charging system is not able to provide full
power at engine idle. As engine speeds are increased,
this condition should correct itself as higher engine
speeds allow the charging system to create maximum
power.
You can only drive for a short time with the readings
outside the normal operating range. If you must
drive, turn off all unnecessary accessories.
Readings outside the normal operating range indicate a
possible problem in the electrical system. Have the
vehicle serviced as soon as possible.Brake System Warning Light
With the ignition on, the brake system warning light
will come on when you set the parking brake. If you
try to drive with the parking brake engaged, a chime
will sound when the vehicle speed is greater
than 5 mph (8 km/h).
Your vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part can
still work and stop you. For good braking, though,
you need both parts working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.
This light may also come on due to low brake uid. See
Brakes on page 5-42for more information.
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